My mum made me feel bad about feeling anxious about going to a Christmas get together with my co-workers

So I have this Christmas get together thing with my co-workers in a few hours where we first go bowling and then having dinner at a restaurant. My boss wrote in the invite: Bowling at 6, then restaurant, and after that we'll see where the night takes us. I'm assuming based on that last part that we might still go somewhere after the restaurant, like to a bar or something. When I told my mum about it I wanted to tell her I'll see how I feel after the restaurant and then decide if I'll come home or continue spending the night with the others (I live really close to the restaurant we're going to so technically I could just walk home if I'm feeling anxious or overwhelmed at that point). I was about to tell her that but before I could do it my mum immediately started saying how I absolutely need to stay all the way through. I then told her that I'll see how I feel at that point, to which she replied that it'll be weird and rude if I leave immediately after the restaurant. She even kept persisting on it after I said multiple times that I don't want to make that decision yet because I don't know how I'll feel at that point.

For some context about my mum: she knows that I've suspected I might be autistic but she doesn't know just how much I actually suspect it. She also knows that social situations often make me uncomfortable and that I'm easily overwhelmed by them. I know that in her mind she's only trying to help me, because I rarely see anyone or have any type of a social life, and she thinks that she's doing the right thing by pushing me to be more social. But I don't think she quite understands how uncomfortable it makes me feel. It makes me feel like I'm supposed to force myself to spend an entire evening with people I barely know, no matter how uncomfortable it makes me feel. I just feel like if I had a child and I knew that social situations can be difficult for them, I would always try to let them know that it's okay to leave early if you feel uncomfortable. It's already a big thing for me that I'm even going in the first place, so I just wish my mum wouldn't pressure me to stay this much.